1. Field of the Invention
The present invention relates to radiation direction adjustable vehicle lamps and more particularly, to a vehicle lamp steering mechanism, which uses a step motor to drive gears, achieving adjustment of the radiation direction of a vehicle lamp.
2. Description of the Related Art
Using gear transmission driving means for biasing a vehicle lamp is known. U.S. Pat. No. 6,648,494 discloses a vehicle lamp, entitled “Vehicle lamp and rotary driving apparatus”, which includes a light source means, a power source means and a transmission unit. The transmission unit comprises a first gear, a second gear, a third gear, a driving gear, a pivot means and a connection plate. The power source is a motor for moving the first gear, the second gear, the third gear, the driving gear, the pivot means and the bracket to bias the light source means, thereby adjusting the irradiation angle of the light source means.
According to the aforesaid prior art design, the driving gear and the pivot means are not arranged in a coaxial relationship. When the driving gear drives the bracket to bias the pivot means, only a part of the driving force of the driving gear is transferred to the pivot means. Thus, the transmission efficiency of the transmission unit is not optimal. An improvement in this regard is necessary.